Paterinata is an
extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
class
Class or The Class may refer to:
Common uses not otherwise categorized
* Class (biology), a taxonomic rank
* Class (knowledge representation), a collection of individuals or objects
* Class (philosophy), an analytical concept used differentl ...
of
linguliform brachiopods which lived from the
Lower Cambrian (
Tommotian) to
Upper Ordovician (
Ashgill). It contains the single order Paterinida and the subfamily Paterinoidea. Despite being some of the earliest brachiopods to appear in the fossil record, paterinides stayed as a relatively subdued and low-diversity group even as other brachiopods diversified later in the Cambrian and Ordovician.
Paterinides had
organo-
phosphatic
In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid .
The phosphate or orthophosphate ion is derived from phosphor ...
shells which were ventribiconvex (both
valves convex, the ventral valve moreso) and strophic (with a straight hinge line). Shell ornamentation usually consists of concentric fila (fine ridges) and tiny pits. The tiny larval shell has a smooth outer halo and strongly ornamented inner portion.
When seen from behind, each valve appears triangular, with a system of superimposed plates and furrows. Each valve has a broad triangular depression edging the hinge, known as a pseudointerarea. The middle of each pseudointerarea hosts a narrower excavation or furrow, known as a notothyrium (in the dorsal valve) or a delthyrium (in the ventral valve). Finally, these furrows may be partially covered by a convex plate-like overgrowth, known as a homeochilidium (in the dorsal valve) or a homeodeltidium (in the ventral valve). The furrow-and-plate pairing creates closed pockets near the hinge, where the pedicle presumably emerged.
The
musculature of paterinides seemingly relied on a small number of broad muscles within the shell. There are a pair of large triangular muscle scars near the hinge of the ventral valve, conjoining under the homeodeltidium. There are two pairs of scars in the dorsal valve, one pair set medially (at the center of the shell) and the other set posterolaterally (further back and outwards). These major scars likely correspond to
adductor muscles, which close the shell. A subtle pit was present at the tip of the homeochilidium, possibly hosting diductor muscles, which open the shell. Diductor muscles are otherwise only found in
articulate brachiopods. The network of
mantle
A mantle is a piece of clothing, a type of cloak. Several other meanings are derived from that.
Mantle may refer to:
*Mantle (clothing), a cloak-like garment worn mainly by women as fashionable outerwear
**Mantle (vesture), an Eastern Orthodox ve ...
canals usually had a saccate form, with a pair of midline canals arcing outwards once they reach the shell margin.
Subgroups
* Order Paterinida
Rowell, 1965
** Superfamily Paterinoidea
Schuchert, 1893
*** Family
Cryptotretidae Pelman, 1979 (Lower Cambrian)
**** ''
Aldanotreta
''Aldanotreta'' is an extinct genus of brachiopods dating from the Tommotian age of the Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. T ...
''
Pelman, 1977 (Tommotian)
**** ''
Askepasma
''Askepasma'' is an extinct genus of brachiopods which existed in what is now Australia and southern China during the Lower Cambrian.
The type species is ''A. toddense''. ''A. transversalis'' occurs in Guizhou, and ''A. saproconcha'' is the olde ...
''
Laurie, 1896 (
Atdabanian
Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambrian Stage 2 and precedes Cambrian Stage 4, although neither its base nor top have been formally defined. The plan is for its lower boundary to correspond approxim ...
)
**** ''
Cryptotreta
''Cryptotreta'' is a genus of tephritid or fruit flies in the family Tephritidae.
Species
*''Cryptotreta cislimitensis'' Steyskal, 1977
*''Cryptotreta pallida
''Cryptotreta pallida'' is a species of tephritid or fruit flies in the genus ''Cr ...
''
Pelman, 1977 (Tommotian)
**** ''
Dzunarzina''
Ushatinskaya, 1993 (Atdabanian)
**** ''
Salanygolina''
Ushatinskaya, 1987 (
Botomian
Cambrian Stage 4 is the still unnamed fourth stage of the Cambrian and the upper stage of Cambrian Series 2. It follows Cambrian Stage 3 and lies below the Wuliuan. The lower boundary has not been formally defined by the International Commission on ...
)
*** Family
Paterinidae Schuchert, 1893 (Lower Cambrian - Upper Ordovician)
**** ''
Dictyonina''
Cooper, 1942 (Lower Cambrian - Upper Cambrian)
**** ''
Dictyonites''
Cooper, 1956 (Lower Ordovician - Upper Ordovician)
**** ''
Kolihium''
Havlicek, 1982 (Lower Ordovician)
**** ''
Lacunites''
Gorjansky, 1969 (Lower Ordovician)
**** ''
Micromitra
''Micromitra'' is a genus of brachiopods known from the Middle Cambrian Burgess Shale. 160 specimens of ''Micromitra'' are known from the Greater Phyllopod bed
The Phyllopod bed, designated by USNM locality number 35k, is the most famous fossil ...
''
Meek, 1873 (Lower Cambrian - Upper Cambrian)
**** ''
Paterina''
Beecher, 1891 (upper Lower Cambrian - Middle Cambrian)
See also
*
*
Tumulduria
References
Prehistoric protostome classes
Paleozoic brachiopods
{{brachiopod-stub